Do probiotics really work?

Probiotic yoghurt drinks have been used for years to treat tummy trouble. Now doctors think they could be a significant weapon against MRSA. RACHEL BAIRD investigates....

PUBLISHED: 00:00, Tue, Feb 12, 2008

0

Traditionally doctors have made people better by killing bacteria but these days they suspect that eating certain bugs could actually help patients.

Hospitals in Brighton are giving probiotic yogurts to those at high risk of infection from the superbug C difficile. And recently, a probiotic powder called VSL3 became available on NHS prescription for patients with digestive problems such as colitis and irritable bowel syndrome (IBS).

Dieticians also recommend probiotics for people who have had a tummy bug or have been taking antibiotics – drugs which kill the “friendly” bacteria that live naturally in the body.

Growing evidence for the benefits of friendly bacteria has led to a booming market of probiotic drinks, yogurts, supplements and powders. But some are much more effective than others.

What are probiotics?

Some are yeasts but most are bacteria similar to the vast numbers that live naturally in the gut. These friendly bacteria help protect against harmful ones.

They also play a role in digestion and help with the development of the immune system. Different probiotic products contain different species, strains and, crucially, different numbers of bacteria.

Which conditions do they help?

“I recommend them for people who have some sort of issue with their bowels, such as bloating, cramps, loose stools, diarrhoea or constipation,” says Catherine Collins, chief dietician at St George’s Hospital in London.

There is also evidence that probiotics can reduce the risk of diarrhoea when travelling abroad and also for those who have been taking antibiotics. Dr Jeremy Sanderson, consultant gastroenterologist at Guy’s and St Thomas’ NHS Foundation Trust in London, says probiotics also seem to help patients with IBS and ulcerative colitis – a disease in which inflammation and ulcers affect the lining of the colon and rectum – although more evidence is needed.

Drugs and surgery are the usual treatments, but Dr Sanderson says he frequently prescribes probiotics too. “In clinical practice, you see the benefit,” he says.

Should healthy people take probiotics?

Ms Collins says that once a gut problem has cleared up, there is no need to keep taking probiotics. But Professor Simon Cutting, of the School of Biological Sciences, Royal Holloway, University of London, says: “Trials show that probiotics also benefit the human immune system.”

Are they harmful?

Rarely but fears were raised recently after 24 patients died in a medical trial by Dutch scientists. Patients with acute pancreatitis were given very high doses of probiotics – equivalent to drinking 1,000 bottles a day.

Which products are best?

For a probiotic to work, enough of the bacteria have to survive the acid in your stomach and get right through to your gut. This is why experts say that a single dose of probiotic should contain at least 10 billion bacteria. Dr Sandra McFarlane, senior research microbiologist at Dundee University, says it’s probably best to take probiotics in capsules with an “enteric coating” to protect them from stomach acid. She also suggests taking probiotics with food to buffer the acid.

But beware. Half the products in one study did not contain what the label said they did. However, probiotics from major manufacturers such as Danone, Yakult and Seven Seas did live up to their claims.

IT WORKED FOR ME

Jane Edwards, an accountant in her 40s, lives in Oxford and has IBS. For the past three years she has controlled the condition by taking probiotic supplements and being careful with her diet.

“For years, I had IBS and it caused chronic diarrhoea. After it was diagnosed I stopped eating sugar, yeast and dairy foods, which helped a bit.

A dietician suggested I try a probiotic supplement to restore the good bacteria in my gut. After I started taking the supplement regularly, there was a marked change and I just got better and better.

Now I exclude dairy foods, but I do occasionally eat things with a small amount of milk and I eat sugar and yeast in moderation.

I still take the probiotic capsules, although I have cut down from two to one a day and the effect is just as good. I couldn’t prove they work unless I came off them for a month. But I think they do and I don’t want to stop them in case the diarrhoea comes back.”